To sit in Xiao Ying’s room in the hutong was to inhabit a space that was first occupied 3,000 years ago in the Zhou Dynasty. Was the uneven brick in the entrance originally part of the courtyard of some ancient official? To get to her room, I remember stepping through an impressive gate, about ten feet high and topped with a curved tile roof. The ever-open gate included a brass knocker in the shape of a dragon, turned black with coal grime. Didn’t it? Memory plays tricks, and I think I may be incorporating a childhood image of Scrooge’s strange door-knocker in an old version of A Christmas Carolinto my memories of Xiao Ying. To find her was impossible without seeming to turn left 20 times before turning right. Wandering roads that become alleys that become nothing more than a wobbly cement path between two high brick walls topped with broken glass. The paths were barely large enough to squeeze past the gawkers who looked aghast at the sight of a foreigner in such a place—a mile and a millennium away from Tiananmen Square.

A few days later, Daddy fell at the mailbox, bounced his head on the pavement, and crawled up the driveway, scraping the skin off his knees before collapsing on the front steps. Mama sat in her recliner in front of the TV, worried and clueless, until a neighbor called an ambulance. The EMTs got Daddy propped up in his recliner. He refused to go with them. When I arrived, Daddy was gulping down whiskey. I called the ambulance back, and they took him to DeKalb Medical. Doctors found prostate cancer and operated. My sister and I cried, sure Daddy was in his last days.

Among the misperceptions about solitary confinement is that it’s used only on the most violent inmates, and only for a few weeks or months. In fact, an estimated 80,000 Americans — many with no record of violence either inside or outside prison — are living in seclusion. They stay there for years, even decades. What this means, generally, is 23 hours a day in a cell the size of two queen-sized mattresses, with a single hour in an exercise cage, also alone.

Dr. Yang had by this point been training with his white crane master for 13 years. When he learned of the scholarship, Cheng put all his cards on the table: If Dr. Yang stayed in Taiwan, he’d teach him everything he knew—a compelling offer, given the zealotry with which most masters guard the secrets of their craft. Still, Dr. Yang declined, preferring a more marketable degree in advanced physics to the antiquated teachings of the white crane.

In 1976 Cheng fell gravely ill, but Dr. Yang’s mother, rightly guessing he’d abandon his studies if he knew, never mentioned it. By the time Dr. Yang found out, it was too late. Standing before his master’s grave three years later, he realized he had failed him in the worst way possible. By his own account, he had picked up only half of his master’s knowledge. The rest was lost forever.

Now Dr. Yang recalled once asking his white crane master how much he had learned from his own master. Wordlessly, Cheng held up the back of his farmer’s hand and blew off an imaginary puff of dust. That image still resonates with Dr. Yang. Every year he visits his master’s grave in Taiwan, by way of penance. The shame has long since become a part of him, he said. It is his goad, his motivator. His whip.

Underwood, of course, covets a gold medal and the fame that would come with it. “I want to take that ride,” she says. “I want to be a household name.”

But beyond that, she wants to be a symbol of hope to anyone who has ever been sexually abused, though to do so requires something harder for her than a thousand hours of hitting the heavy bag. She has to talk about what happened.